Yellow Polyps are are a close relative of Zoanthus and Palythoa from the Genus Parazoanthus. There are several species of Parazoanthus in the wild, but the most commonly seen species in the reef aquarium hobby are the bright yellow Parazoanthus gracilis. Yellow Polyps are fairly easy to keep. They tolerate a wide range of lighting intensities and water conditions. Once settled in, they multiply quickly. Please see below for more care tips for Parazoanthus polyps as well as checking out our Top 5 Tips for setting up a reef.

Location

Yellow Parazoanthus polyps are harvested mainly from the islands of the Indopacific including Fiji, Tonga, Solomon Islands, and the Great Barrier Reef. Their color is the standout feature of yellow polyps. Bright yellow coloration is one of the more difficult colors to come across in reef keeping.

Lighting

Yellow polyps are not as demanding as other corals when it comes to lighting. They can be kept under a wide variety of lighting types, and are tolerant of both low and high light conditions. What I have noticed though is their color and size changes dramatically depending on the intensity of light.

When provided low light, say 50 PAR and under, the polyps take on a mustard yellow color and the polyp itself grows in size with fuller polyp extension. Under more intense lighting over 150 PAR, the polyps develop a canary yellow color and shrink down to a quarter of their original size.

Light also plays a big role in our viewing of them in the aquarium. In this day and age, reef hobbyists tend to go much heavier into the actinic range. This should come as no surprise because actinic light shows off the incredible fluorescence of a multitude of corals. Doing that with yellow polyps however will be highly disappointing as they are essentially non-fluorescent and all of their bright yellow color will be lost in favor of a muted grey blue color. To appreciate the full intense yellow coloration of these polyps, you will need to provide daylight coloration between 6,500 and 10,000 Kelvin.

It is always wise however to acclimate new arrivals in lower light areas because it is far more likely to be damaged from overexposure than starve from underexposure.

Low Light Low light translates to about 30-50 PAR

Medium LightMedium Light is between 50-150 PAR

High LightHigh Light is anything over 150 PAR

Lighting is a loaded topic, so for a more in-depth discussion of lighting, please see our Deep Dive article.

Water Flow

Moderate to high water movement is recommended. Yellow Polyps benefit from enough flow to keep detritus from settling on them.

Feeding

While Parazoanthus derive much of their energy from the products of their zooxanthellae, they do have the ability to capture prey. You really do not need to go out of your way to spot feed this coral because they are some of the most capable corals when it comes to prey capture. Their tentacles are highly effective at grabbing food out of the water column and the very act of feeding your tank will provide plenty of opportunities for yellow polyps to grab what they need. I’ve seen them grab up both dry food as well as frozen food and they can ingest anything up to a mysis shrimp in size.

Propagation

Yellow Polyps have been propagated extensively in captivity and are an excellent candidate for aquaculture. It is reasonable to believe that a sustainable harvest can be achieved in time.

Acclimation

Proper acclimation is extremely important considering the stress imposed on the animals by the shipping process. Please take a moment to review our Acclimation Guide.

Photography

The images were taken with a Canon 5D mk II and 100mm macro lens under T5 Fluorescent lighting. Quite a lot goes into how we go about shooting the corals and anemones you see on Tidal Gardens. For an in-depth look at our methods, check out our comprehensive Reef Aquarium Photography FAQ.